would expand the reporting of joint gap measurements to include large diameter pipes above 48 inches . If this proposal proceeds , contractors and CEIs will soon be haggling over the accuracy or acceptability of 1 / 16 inch beyond the joint gap criterion of 72-inch diameter or larger pipe .
The roots of FDOTs joint gap criteria date back to at least 1973 . At that time , the joint gap was measured as the pipe was being laid and prior to the soil envelope . The gap measurement specification was conceived in a pre-CCTV inspection era and was presumably a surrogate or indicator for joint performance once the pipe was operational . In the present , the use of CCTV inspections allows the observation of the joints ’ performance in lieu of a gap measurement .
It is a common means and methods of pipe installation that contractors inspect the joint gap as the pipe is set , and then make adjustments to the joint before placing the soil envelope . The joints are also wrapped with a geotextile having a specified opening size amongst other parameters . In 1973 , it was less burdensome to re-home a pipe joint because circumstances where that it was done before the soil envelope and backfill were placed . Now , 50 years later , it is much more burdensome for a contractor to replace a pipe for a joint gap infraction – regardless of joint performance - after it has been backfilled . Present inspection methods allow for the installed joint of all types of pipes to be inspected based on performance , at which point the Repair
Matrix and engineering judgment can be applied .
The Department has the duty to inspect all pipes to observe present performance and attempt to forecast service life . All gasketed pipe joints – whether concrete , metal , plastic , or hybrid - perform based on gasket compression . Some pipes even indicate a homing mark for this reason . The contractors understand the means and methods of inserting pipe joints . We have modern inspection practices to verify pipe joint performance . It ’ s time to eliminate the burden on the contractors caused by the 1973-era requirement to measure concrete pipe joint gaps .
Voice Your Comments to the FDOT
FDOT is allowing comments to 4300201 ( Pipe Culverts ) until September 14 . Please use this LINK to submit your comments ( scroll to bottom of table ).
SEPTEMBER 2023 • DITCHMEN 5